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Comment: Re:I remember Y2K, do you? (Score 1) 95

by bobbied (#46784039) Attached to: Lack of US Cybersecurity Across the Electric Grid

We have been discussing a cyber attack on the power grid Just so it's clear..

There are likely not many people that have any interest in taking out the power grid.

We part ways on that statement. There are *countries* where you would be hailed as a hero if you did this. Countries where they would gladly pay great sums to anybody who could actually *do* this at their bidding. So I hope you see how wrong you seem to me on your above statement.

Full stop now... Don't think we are getting anywhere now..

Comment: Re:The perils of not RTFA (Score 1) 335

Half the posters automatically assume that snowden is working for the other side and that he's part of a negative propaganda campaign against the US.

How scary is the world you live in? It's like the brains can't process the possibility of something not having an ulterior motive.

So, are you saying it's *possible* that all this wasn't just a setup by Putin? Yea, and it's *possible* for the sun to rise in the west...

If you think Putin would willingly subject himself to questioning by Snowden, when he didn't have a really good idea what he was going to be asked and how he was going to answer, and that Snowden was free to ask any question that crossed his mind, you need to get your tinfoil hat back on...

Comment: In Mother Russa... (Score 3, Insightful) 335

Even the questions you can ask are provided by the state..

OF COURSE it was scripted and likely highly edited. This is 100% propaganda aimed squarely at the west by Putin. Snowden is just being used to attract attention and shape the message. He's just a pawn in a much larger game.

Reading between the lines though, I wonder what Putin is up to. Why bother with this?

Comment: Re:Snowden never had integrity (Score 0, Troll) 335

He's a traitor and a corrupt piece of crap. He's caused more harm to world peace than even Putin. The two certainly belong together.

Where I agree he's a traitor... I think you ascribe him way too much power. Snowden is, at this point, just a pawn being used by Putin.

Comment: Re:Not so fast, Thermodynamic laws are pesky thing (Score 1) 155

by bobbied (#46778839) Attached to: 'Thermoelectrics' Could One Day Power Cars

You fell for the "waste heat" argument garbage didn't you... So sorry.

The conversion of heat energy to another form (electricity in this case) requires the TRANSFER of heat from a source to a sink. What we "dump" in the sink is called "waste heat" but that does not imply it is somehow useable to produce more power output from the plant (assuming a modern power plant). The most efficient conditions for an idea heat engine is when the heat is transferred at a constant temperature and in modern power plants they go to great lengths to approach this ideal.

Thermoelectrics generally require fairly high temperature differentials to operate. By the laws of thermodynamics, this means that they are never going to be efficient, and trying to use them in a power plant simply cannot be helpful to it's efficiency. Sorry, the laws of thermodynamics still apply here.

Comment: Re:Not so fast, Thermodynamic laws are pesky thing (Score 1) 155

by bobbied (#46778737) Attached to: 'Thermoelectrics' Could One Day Power Cars

nothing to do with heat engines. THERMOELECTRICS.

Which are subject to the laws of Thermodynamics even if you don't think so....

Your claim is like saying because it's solid state, it has nothing to do with electric fields... Totally and completely false.

Claims like this is where perpetual energy scams get started. "Hey, look at this design, Energy for FREE! (Thermodynamics just *don't* apply.)"

Comment: Re:Not so fast, Thermodynamic laws are pesky thing (Score 1) 155

by bobbied (#46778681) Attached to: 'Thermoelectrics' Could One Day Power Cars

The article never talked about massive gains in heat efficiency for power plants, just scavenging waste heat.

You are falling for the waste heat argument. Power is generated by the transfer of heat from a high temperature source to a low temperature sink. In a power plant, we've managed to engineer them pretty well and we get pretty close to the ideal. Any new device will have to exceed the existing efficiency or it simply will not help, but hurt. Remember it is the TRANSFER of heat that is used to produce power, not the heat energy itself. So the "dumping of waste heat" is not a power loss in the system where you can hope to get gains from.

If you are familiar with the ideal cycle, remember that this cycle requires the transfer of heat to and from the working fluid/gas at a constant temperature. The devices being described require fairly high temperature differentials to operate. They simply *cannot* be as efficient because of this, and if I understand the physics, they will never really be all that more efficient than they are now.

Comment: Re:Not so fast, Thermodynamic laws are pesky thing (Score 1) 155

by bobbied (#46778585) Attached to: 'Thermoelectrics' Could One Day Power Cars

The article mentions power plants near the end.

Where I'm dubious about the usefulness of this technology in cars, I would agree that there is at least a possibility it could help. Thermodynamics would allow it. However, in a power plant, Thermodynamics tell me they are not useful.

I also wonder if the original author and the researchers involved actually understand the issues, given they try and present this as a way to improve a power plant. On that point they are totally and obviously mistaken. If they are that far off on that point, I have to start questioning the rest of their ideas because they are obviously either ignorant or deliberately misleading.

Comment: Re:Not so fast, Thermodynamic laws are pesky thing (Score 2) 155

by bobbied (#46775733) Attached to: 'Thermoelectrics' Could One Day Power Cars

The maximum limit on an an arbitrary heat-conversion system is that doesn't break accepted theory is the Carnot-cycle heat engine, where eff 1 - T_cold / T_hot (as measured from absolute 0). But it's a rare real-world engine that gets anywhere near the Carnot efficiency limit - a car engine might run at 1100K for an ideal efficiency of around 73%, but the reality in most cars is closer to 25%. Being solid-state a thermoelectric device could potentially operate at very near the ideal (no mechanical losses), roughly tripling the efficiency. Assuming 90% efficient electric wheel motors the total system efficiency could be nearly as high.

Don't be fooled that "hey they are solid state and convert directly to electricity". Deep down, it's still a physical process that produces electricity, even if the moving parts are not something you can see. In actual practice, what happens with these things produces horrible efficiency.

These electronic devices are semiconductor junctions that you get heat to flow through in hopes the electrons will bounce their way across the junction into the cooler side and get stuck... They are not efficient from a thermodynamic perspective, and unless my physical understanding of how they work is totally wrong, they are never going to approach the efficiency of even an internal combustion engine, from a thermodynamic perspective anyway.

Comment: Re:Not so fast, Thermodynamic laws are pesky thing (Score 2) 155

by bobbied (#46775663) Attached to: 'Thermoelectrics' Could One Day Power Cars

Before you make a bigger ass of yourself, please look up what "waste heat" actually is and familiarize yourself with the "Thermo" in thermodynamics.

Engines run HOT. Every bit of heat that travels into the metal and outside the engine is lost energy. Capturing bits of that lost energy and putting it to good use is the concept here. This is waste heat, so it is free, just as eating food out of the garbage bin is "free food" -- someone else paid for it, but they threw it out so it is "free" for you. It's not disobeying thermodynamics any more than burning a gallon of gasoline to make a car move 30 miles is disobeying the laws of thermodynamics.

For other automotive-related things that defy your idiotic concept of physics, please see turbochargers and hybrid cars.

If you read my post.... (and apparently you didn't) ... I specifically stipulate that automotive applications *might* be successful and worth of investigation. The reason I say this is because of the huge amounts of heat transferred out the tail pipe and radiator in a modern internal combustion engine at sometimes very high temperature differentials leaves something to recover. This is totally unlike a modern power plant, where heat transfer has been carefully engineered to be as efficient as possible, thus leaving little room for thermodynamic improvement. However, my doubts about automotive application are over costs, weight and complexity not about the Thermodynamics of the application.

Comment: Re:Not so fast, Thermodynamic laws are pesky thing (Score 1) 155

by bobbied (#46775609) Attached to: 'Thermoelectrics' Could One Day Power Cars

Until these devices they describe approach the current efficiency of a power plant, there is zero chance they will be helpful on an industrial scale. Modern power plants are usually within a few percentage points of ideal so these devices are going to have to come way up the efficiency scale, and they are horrible now. Given how they work at the subatomic level (holes, electrons etc) I seriously doubt we are in any danger of reaching this level.

Comment: Re:Not so fast, Thermodynamic laws are pesky thing (Score 1) 155

by bobbied (#46775567) Attached to: 'Thermoelectrics' Could One Day Power Cars

I'm not sure how the cooling works for PV cells. But, if they are actively cooling the liquid there is little to be gained from this arrangement and it is likely going to lead to hotter cell temperatures and cooler liquid temperatures.

So it *might* work, but only if the temperature differential they can stand is high enough and they are not expending energy to cool the liquid through some heat engine.... (I.e. if they use something like a swamp cooler or something.)

Never appeal to a man's "better nature." He may not have one. Invoking his self-interest gives you more leverage. -- Lazarus Long

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